As Prime Minister Shinzo Abe offered to extend broader economic cooperation to Russia in his talks with President Vladimir Putin in Sochi on May 6, attention was focused on whether Japan can find a path to resolution of a decades-old bilateral dispute over the sovereignty over the Russian-held Northern Territories.

It has proved no easy task, however, to make progress on the territorial issue, as the two countries remain far apart over the matter.

"I'm very glad to have had a meeting with you, Vladimir. Our bilateral relations have become active since our last summit in September last year. I appreciate having been communicating with you, Vladimir," Abe was quoted as telling the Russian president, calling Putin by his first name twice.

In contrast, the Russian president called Abe, "Your Excellency the Prime Minister."

Abe spoke to Putin in a friendly manner because he believes that Japan can resolve the issue of the Northern Territories only through summits with the president, who has broad power.

Prime Minister Abe viewed the latest visit to Russia as an important step toward making progress on bilateral ties.

During their summit talks, Abe offered an eight-point agenda of economic and other cooperation to Putin in a bid to lay the groundwork for resuming negotiations toward settling their territorial dispute.

Since it has been difficult for Tokyo to relax sanctions it imposed on Moscow following the outbreak of the Ukrainian crisis out of consideration for the United States, which led the punitive measures, Japan has offered a wide range of cooperative programs, centering on those led by the private sector.

Regarding the development of the Far Eastern area, to which Russia attaches particular importance, Tokyo offered measures to promote industries through the development of port and harbor facilities and agricultural development.

The prime minister's office apparently played a leading role in working out these programs at the instruction of Prime Minister Abe, who a prime minister's office source says "has shown extraordinary enthusiasm about his meeting with Putin."

The summit talks in Sochi symbolize improved bilateral ties. Russia appreciated the fact that Abe attended the opening ceremony of the Sochi Winter Olympics in February 2014 while the leaders of other Western countries did not do so because they were critical of Russia's human rights situation.

Relations between Japan and Russia worsened over the Ukrainian crisis and sanctions that Tokyo imposed on Moscow over the crisis. At the latest summit, however, the two leaders aimed to share the view that the bilateral relations have improved to pre-crisis levels.

While European and North American countries imposed severe sanctions on Russia, such as banning major Russian banks from raising funds in European and North American financial markets, Japan imposed only limited sanctions such as the suspension of some inter-governmental talks and issuance of visas for Russian VIPs. It is widely believed that Japan can implement the cooperative programs that Abe offered to Putin at the latest talks while retaining these sanctions.

Since he took office in December 2012, Prime Minister Abe has attached particular importance to nurturing mutual trust with Putin and has continued top-level diplomacy with the Russian leader. The latest summit was the 10th during Abe's current term as prime minister. He had three such meetings when he was previously in power for approximately one year from 2006 to 2007.

Under normal circumstances, Putin would have visited Tokyo following Abe's visit to Sochi in 2014, but a visit by Putin to Japan has been postponed indefinitely.

Abe attempted to draw a positive response from Putin by visiting Russia again and offering fresh cooperation programs to Russia. Tokyo is also considering inviting Putin to Yamaguchi Prefecture, Abe's hometown.

However, Itsuro Nakamura, a professor of Russian politics at the University of Tsukuba says, "Under the current circumstances, it's difficult to think Russia will compromise in territorial talks."

It remains to be seen how far territorial negotiations between Japan and Russia will progress even if overall bilateral relations, including economic and cultural ties, improve through top-level diplomacy. As such, Japan is trying to strengthen bilateral relations while pursuing ways to settle the territorial dispute though it has no clear prospects.

Moscow has stuck to its stance that the four islands belong to Russia.

"Japan should confirm the outcome of World War II," Russian Foreign Minister Sergey Lavrov told his Japanese counterpart on April 15. Tokyo argued that the four islands are inherently territories of Japan. The Putin government, however, has no intention of compromising its claim on the Northern Territories, while demanding that Japan compromise over the issue.

Russia demands that Japan first and foremost acknowledge that the former Soviet Union and Russia lawfully made the four islands their own territory as a result of World War II and that bilateral territorial negotiations be based on the Soviet-Japanese Joint Declaration of 1956, which states two of the four islands be returned to Japan after a bilateral peace treaty is signed.

Alexander Panov, former Russian ambassador to Japan, says, "President Putin has proposed that bilateral talks be based on the 1956 declaration, and is apparently not prepared to make any further compromise."

Russia is becoming increasingly unlikely to compromise over the territorial issue because domestic public opinion and the Putin administration's stance have changed since the country's annexation of Crimea in March 2014.

Putin emphasized that it is "historical justice" for Russia to annex Crimea, which had previously been part of Russia's territory, winning strong support from the Russian public. Russian people are taking an increasingly tough stance on territorial issues.

Moreover, while Russia is in conflict with Western countries over the Ukrainian issue, the Putin government has maintained that Russia's victory over Germany and Japan in World War II is proof that Russia has had "justice." With regard to the dispute over the Northern Territories, Moscow emphasizes that Japan is the only country that does not accept the results of the war.

Dmitri Trenin, director of the Carnegie Moscow Center of the Carnegie Endowment for International Peace, points out that it is becoming increasingly difficult to settle the territorial dispute in a way that could be viewed as Russia ceding part of its territory.

At the same time, Trenin says, "The person who annexed Crimea may be able to hand over a small territorial area to another country."

It is now difficult for the Russian government to compromise in diplomacy as a lower house election is scheduled for this coming September and the next presidential election is to be held in 2018. Hardline opinions that Russia should not hand over any of the four islands to Japan also persist.

However, the Russian economy has slumped due to sanctions imposed by Western countries and a decline in crude oil prices, and is increasingly dependent on China both in diplomacy and economy. These situations could threaten the foundations of the Putin administration from a mid- and long-term perspective.

Russia is believed to be intent on using the territorial issue to draw maximum concessions in the economic and other fields from Japan.